Air conditioning apparatus



April! 23, 1935'. s. M. ANDERSON 1,999,148

AIR CONDITIONING APPARATUS Filed Sept. 7, 1934 2 Sheecs--Shee v 1 I11 06 nior 6A MUEL M. A/vamzso/v April! 23, 1935. s. M. ANDERSON AIR CONDITIONING APPARATUS Filed Sept. 7, 1954 2 Sheets-Sheet I f/0671501 5A Ml/[L N. ANDERSON g @40 J Patented Apr. 23 i935 Ultit fiWATEfi l,999,ll l8 Alllit coN rrroNrNa arrana'rps Samuel M. Anderson, Sharon, Mass.,- assignor to 1E. 1F. Sturtevant Gornpany, llnc., Hyde llarlk,

Boston, Mass.

Application September '7, 1934, Serial No. 743,051

3 Claims.

This invention relates to methods and apparatus for the conditioning of air, and relates more particularly to a system for heating and cooling air which is circulated through railway passenger cars.

This invention is an improvement over that disclosed in my joint application Serial No. 733,- 734, filed July 5, 1934.

There are many difficulties in the proper conditioning of air for railway passenger cars that are not present in the air conditioning of stationary enclosures, such as motion picture theaters, for example. One difiiculty is the proper arrangement of the apparatus for efiicient conditioning and distribution of the air. Another difficulty results from the shape of the car in that it is difiicult to distribute the conditioned air equally and without drafts.

It is customary at the present time to place the air conditioning apparatus for supplying proper conditioned air to the passenger space at one end and in the roof zone of the car, the conditioned air being forced through one or more longitudinal ducts extending the length of the car and discharged from a plurality of spaced outlets along the car length. The difiiculties in this arrangement are improper distribution and the production of drafts. When the relatively few discharge outlets of the duct or ducts were made of sufficient size to permit a low outflow velocity, distribution was almost entirely uncontrolled and resulted in unequal delivery from the various openings. Usually the space nearest the conditioning unit was served with too much air and the space at the other end of the car was provided with an inadequate supply of air. When the openings were made small enough to dam back the air fiow so as to produce a static pressure extending the full length of the duct, velocities from the open-' ings were too high and produced unpleasant drafts.

Another difiiculty resulting from the peculiar shape of the car where longitudinal supply ducts were used, isdue to the fact that even though proper air distribution was obtained in the ducts, those passages nearest the air conditioning unit still received too greatan effect from the conditioned air because they were contacted with not only by the air discharged in their immediate vicinity, but by recirculated air passing them and discharged at other points in the car, on its way back to the recirculated air inlet in the conditioning chamber. Furthermore, at'the end of the car opposite from that in which the air conditioning chamber was mounted, the end of the car created a back pressure which interfered with the discharge and proper circulation of the air discharged in that area. According'to another feature of this invention, the outflow of the conditioned air is controlled by having the conditioned air built up under static pressure in a main longitudinal supply duct from which it flows at high velocity into an auxiliary duct, from which it then flows at a desired velocity into the passenger space of the car. The air is discharged into the passenger space from a plurality of spaced openings in the ducts, but these openings are not equally spaced along the length of the car, but are so arranged that they are spaced progressively closer together as their distance from the air conditioning unit in one end of the car increases. This insures that more conditioned air is discharged at points further from the conditioning unit, with the result that the combined efiect produced by the air discharged immediately at a given point and that produced by the recirculated air passing that point on its way back to the unit is sufficient for comfort purposes.

The ordinary railway passenger car is equipped with baggage racks which extend into that area within a car between the roof zone and the passenger space. Heretofore, the conditioned air leaving the longitudinal supply ducts in the cars equipped with air conditioning equipment has been discharged in contact with the baggage racks, which, together with the baggage placed on them, has interfered with the air flow, by creating turbulence and damming of flow, resulting in uneven distribution. According to another feature of this invention, a longitudinal supply duct is arranged with outlets which guide the discharged air so that it misses the baggage racks of the car, and yet passes completely into all of the passenger space to provide adequate and equal air distribution.

An object of the invention is to so guide the air discharged from the longitudinal supply duct in a railway passenger car that it avoids the baggage racks arranged in the upper portion of the car.

Other objects of the invention will be apparent 'from the following specification, takentogether with the drawings.

The invention will now be described with reference to the drawings, of which: A

Fig. 1 is a plan view in section, looking down on an air conditioning compartment and a portion of an air discharge duct according to this invention;

Fig. 2 is a sectional, profile view of the apparatus shown by Fig. 1;

Fig. 3 is a diagrammatic view showing the refrigeration and steam supplies connected to the air conditioning apparatus of Figs. 1 and 2;

Fig. 4 is a sectional view of a supply duct according to this invention;

Fig. 5 is a planview with portion of bottom removed, looking upwardly on the bottom of and Fig. 6 is a partial sectional view of a railway passenger car equipped according to this invention.

The air conditioning chamber indicated generally by l l is mounted in one end and in the roof zone of the car. The chamber contains the blower l2, the filter l3, the pre-cooler coils I4,

-the main cooler coils l5, and the steam heating coils IS with which is associated the steam humidifier l1.

As shown by Fig. 3, steam for the coils l6 and humidifier I1 is supplied from the steam source l8, which may be generated locally on the car or may be supplied from a steam locomotive. The refrigerant compressor I9 is driven by the electric motor 20, which may, in turn, be energized from an axle driven generator or from a head-end power supply. A refrigerant, such as Freon, is compressed in the compressor, then passes into the compressor coils 2|, over which the motordriven fan 22 passes a current of air, and thence through the expansion valve 23, where it is expanded in the air cooling coils i acting as evaporator coils. The refrigerant next passes through the pre-cooling coils 24, in which any unevaporated liquid leaving the coils I5 is completely evaporated, and is then returned to the refrigerant compressor I9. That portion of the refrigerant evaporated in coils 24 acts to pre-cool the-air passing through the compartment I I, thus making use of the complete evaporation to secure efficient results.

For the purposes of air distribution, a main, centrally located, air distribution duct 25 is used. As shown more clearly by Figs. 4-6 inclusive, the main duct 25 is provided, in its lower wall, with a plurality of circular openings 26 which discharge into the space 2i which opens into the; auxiliary duct 28. The auxiliary duct 28 is provided in its side walls with the plurality of vents 29, side views of which are shown more clearly by Figs. 2 and 3. Placed above the side vents 29 are the deflecting plates 30, which act to guide the discharged air, as shown by Fig. 6, to avoid the baggage racks 3|.

In operation, the blower l2 passes mixed recirculated and outside air through the filter l3 and over the heat exchange coils in the compartment II, and forces the conditioned air, under pressure, into the main discharge duct 25. Due to the fact that the discharge duct 25 has but the small openings 26 through which the air can leave under the pressure of the blower, a considerable static pressure is built up within the duct 25, with the result that the volume of air leaving the openings 26 most remote from the blower I2 is the same as that leaving the openings 26 nearest the blower l2.

Due to the static pressure within the duct 25, the air passing from it through the small openings 26 is discharged under pressure, and the static pressure in the duct 25 is converted into velocity energy and is discharged into the auxiliary duct 28. The air flowing into the auxiliary duct 28 is baiiied by the walls of this duct so that a small static pressure is built up in this duct with the result that the air is discharged into the passenger space of the car through the spaced vents 29 at relatively low velocity, but with sufficient pressure to cause it to take the path indicated by the arrows of Fig. 6, the physical constants of the apparatus being so proportioned that the velocity of the air is relatively small by the time it reaches the heads of the passengers, with the result that no unpleasant drafts are experienced when cold air is supplied.

As before stated, the deflector plates 30 guide the conditioned air so that, as shown by the arrows of Fig. 6, it just misses the maggage racks 3|, with the result that neither the racks themselves nor the baggage placed upon them cause interruption in the air flow.

As illustrated by Figs. 5 and 6, the main duct 25 is placed above the ceiling 32 of the car, while the small auxiliary duct 28 is arranged to extend a small distance below the ceiling in the center of the car.

Whereas one embodiment of the invention has been described for the purpose of illustration, it should be understood that the invention is not limited to those details described, since many modifications may be made by those skilled in the art after having had access to this disclosure without departing from the spirit of the invention.

What is claimed is:

1. Air conditioning apparatus for a railway passenger car having a ceiling, comprising an air conditioning compartment, means for passing air to be conditioned through said compartment, means for supplying a heat exchange medium to' said compartment, a main supply duct arranged above said ceiling and extending longitudinally of the car, an auxiliary supply duct arranged below said ceiling, a plurality of relatively small openings in said main duct and extending longitudinally thereof and opening into said auxiliary duct, a plurality of relatively large, spaced openings in a side wall of said auxiliary duct for discharging conditioned air to the passenger space of the car, and deflector plates above said openings in said auxiliary duct for deflecting the discharged air in a downward direction.

2. Air conditioning apparatus for a railway passenger car, comprising an air conditioning compartment, means for passing the air to be conditioned through said compartment, means for supplying a heat exchange medium to said compartment, a main dischargeduct connecting with the discharge outlet of said compartment, an auxiliary duct associated with said main duct, means for building up a substantial static pressure in the air in said main duct and for discharging same at relatively high velocity into said auxiliary duct, means for discharging air at relatively low velocity from said auxiliary duct towards a side of said car, and means for deflecting the air discharged from said auxiliary duct in a downward direction.

3. Air conditioning apparatus for a railway passenger car equipped with baggage racks on each side of the car and overhead the passenger space, comprising an air conditioning compartment, means for passing the air to be conditioned through said compartment, means for supplying a heat exchange medium to said compartment, a main longitudinal duct extending down the center of the car and overhead the passenger space, an auxiliary duct mounted below said main duct, means for building up substantial static pressure in the air supplied to said main duct and for discharging same at relatively high velocity to said auxiliary duct, means for discharging the air at relatively low velocity from said auxiliary duct towards the sides of the car, and means for deflecting the air discharged from said auxiliary duct in a downward direction to just miss said baggage racks.

" SAMUEL M. ANDERSON. 

